Pedal-action for pianos.



N0. 65|,749. Patented lune l2, I900.

J. DIERDORF.

PEDAL ACTION FOB PIANOS.

(Application filed Sept. 15. 1899.)

/N VE N TOR ATTORNEY.

THE NORRIS PETERS co" PHOTO LI:THO., wasmumuu. '0. c.

UNITED STATES PATENT OFFIon.

- JOHN DIERDORF, OF INDIANAPOLIS, INDIANA.

PEDAL-ACTION FOR PIANOS.

SPECIFICATION forming part of Letters Patent No. 651,749, dated June 12,1900. Application filed September 15, 1899. Serial No. 730,565. Nomodel-l To all whmn it may concern:

Be it known that I, J OHN DIERDORF, a citi-' Zen of the United States,residing at Indianapolis, in the county of Marion and State of Indiana,have invented certain new and useful Improvements in Pedal-Actions forPianos, of which the following is aspeeification.

The object of my invention is to produce a new pedal-action for pianos,one which will be simple in construction, easily attached or detached,and one in which any lost motion through wear may be quickly and readilytaken up. In all pedals now used in pianos, defects appear from time totime during their use by the different parts becoming worn, which inturn retards and interferes with the action of the pedals, as well asproducing squeaking sounds, which it is the paramount object to overcomeand on which a constant vigilance is kept by all piano manufacturers.When, however, a pedal in a piano shows signs of wear, to remedy thesame is'accompanied by considerable labor. To overcome these obstaclesis one of the objects of myinvention by being able to take up all lostmotion by simply tightening the tension by means of a nut on the rods.There are other features, all of which will be hereinafter moreparticularly described and then pointed out in the claims.

Referring to the accompanying drawings, which are made a part hereof,and on which similar numerals of reference indicate similar parts,Figure 1 is a front elevation of the lower portion of a piano, the frontwall of the piano under the pianoforte being removed, so as to allow aninterior view of the main body of the piano, as well as to show theposition occupied by my invention therein. Fig. 2 is a side elevation ofthe combined parts constituting my invention, the same, being on anenlarged scale.

tone.

Fig. 3 is a rear,

that connects the pedal with the bell-crank. Fig. 5 is an under sideview of that portion of the pedal that contains the corrugations whichreceive the elongated head on the upright rod and shows the manner inwhich said rod may be adjusted longitudinally with the pedal; and Fig. 6is a fragmentary top plan view of the rear end of a .pedal, showing thenotch formed in the end thereof, to-

gether with its connection with the standard.

secured to the floor 2 are the standards 3,

which form the pivotal point for the pedals. I have shown three pedalsin my construction, this being the usual number employed in uprightpianos. The pedals, through the different mechanism employed, effect thehammers and dampers in a piano, thereby bringing'about a greater or lessvolume of The exact manner in which the upright rods 24 (common in allpianos) manipulate the mechanism to bring about these results is old andwell'known by those skilled in the art of piano construction, andtherefore said standards has a horizontal slot 4 cut therein, whichslot after extending a short distance into said standard turns downwardor at right angles with the horizontal portion and which forms a seatfor a pin 5, which passes transversely through the pedal. A thumb-screw6, mounted in a vertical manner in the standard 3, seats itself on thepin 5 when the same is in position, and thereby a tension is secured forthe pedal, as well as to prevent the pedal from disengaging itself fromthe standard 3. After the pedal is placed in position and thethumb-screw6 adjusted the screw is locked by the jam-nut 7, which screwseats itself upon the standard 3.

The pedals in shape are like the ordinary piano-pedal, except at theirrear end a notch Sis formed therein, the notch 8 beingbest shown in Fig.6. The upright portion of the standard 3 passes between the outer wallsof the pedal, which remain after the notch Sis formed and whichconstruction insures a firm bearing for the pedal, and while the pedalis allowed a free vertical reciprocating movement it prevents anysidewise or twisting movement.

The pedals have central thereto and longitudinally therewith a slot 9.On the under side of the pedals, that part through which the slot 9extends, a series of lateral corrugations 10 is formed. (See Fig. 5.)The slot 9 is always of a length equal to the number of corrugations.The corrugations 10 form a seat for the elongated integral head formedon the upright 11, whereby said rod may be moved longitudinally with thepedal and through which means a variety of leverages may be secured forthe pedal. The rod 11 has an elongated head formed on each end thereofand through which the pedal is connected to the bell-crank 12. Inattaching the rod 11 to the pedal the elongated head on the lower end isturned so as to stand parallel with the pedal or the same as the slot 9when the head is passed through the pedal and is then turned crosswisethereto, it then engaging with one of the corrugations 10, whichprevents the said head moving after once positioned and after a tensionhas been placed on the rod 11. The head on the upper end of the rod 11engages with the forked end of the horizontal portion of the bell-crank12. The bell-crank 12 is mounted in the standard 13, which standard isrigidly secu red to the floor 2 of the piano. The bell-crank 12 has anextended integral flange or rib 14:, which rib extends down in a slot 15in the upper end of the standard 13 in a longitudinal manner therewith.The rib 14: on the crank 12 has a series of holes therein, whereby thepivotal point of the bell-crank may be changed, thereby increasing ordecreasing the leverage of said cranks. A pin 16 passes through one ofthe openings in the rib 14 and rests in a slot 16 in the upper end ofthe standard 13, the slot.

16 being at right angles to the slot 15 in said standard. When it isdesired to change the leverage of the crank, the pin 16 is withdrawn andthe bell-crank moved along in the slot 15 until the next hole comes inview, when the pin 16 is inserted. The termination of each end of thebell-eranks is slotted a short distance (see Fig. 3) and also has alaterally-formed cup therein. (See Fig. 2.) This cupped formation on theouter end of the horizontal portion forms a seat for the elongated headon the upright rod 11, while the one on the perpendicular por tion formsa seat for a half-round bearingstrip 17, which strip is preferably madeof a substance less dense than metal, such as wood or the like, and willprevent sounds issuing from thejointconstructed in this manner duringthe operation of the parts. Theflat side of the bearing-strip 17 forms aseat for the wing-nut 18, which is screwed on the rod 19, which rodconnects the bell-crank 12 with the bell-crank 20. The rear end of therod 19, where it connects with the bell-crank 20, has an elongatedintegral head formed thereon and is connected to said crank 20 in thesame manner as the rod 11 connects with the crank 12. The rod 19 at itsfront end connects with the perpendicular portion of the bell-crank 12and is threaded so as to receive the wingnut 18. The bell-crank 20 ismountedin the same manner as the crank 12, except that it stands in areverse or opposite direction from the crank 12. Should any lost motionoccur between the cranks, the same may be readily taken up by thewing-nut 18 on the shaft 19.

A pin 21 passes transversely through the crank 20 and rests in verticalslots in the standard 22, similar to the pin 16 in the standard, onlythat the ends of the pin 21 project some distance on each side of thestandard 22. (See Fig. 3.) The object of projecting the ends of the pin21 is to form a contactpoint for the spring 23, which spring crosses thefront of the standard 22, then around the ends of the pin 21, and upwardto a point slightly below the cupped formation of the perpendicularportion of the bell-crank 20, where the ends of the spring are turnedinward toward each other and rest on the face of the bell-cran k. Thespring 23 insures to a greater degree the prompt return of all parts totheir normal position when the pedal is released and also maintains atension on the parts between the crank 20 and the pedal.

On the outer end of the crank 20 rests an upright rod 24. These rods areemployed in all upright pianos and are usually three in numher, or thesame number as there are pedals, in which one red is located in one endof the piano and two in the other. In Fig. 1 I have shown the end inwhich the one rod is employed, the framework of the piano being brokenaway, so as to leave the parts exposed, this end being considered moresimple and less liable to confusion. The same construction of parts isused in the other end, however, the parts therefore beinginterchangeable. The description of one side is sufiicient for all.

The rod 2% extends up into the piano and affects the hammers and dampersin the same manner as is done in all upright pianos, and, as previouslystated, as my invention does not relate to that portion the same willnot be described.

Having thus fully described my said invention, what I desire to secureby Letters Patent 1s 1. In a pedal-action for pianos, in combinationwith the main piano-body, a standard "rigidly secured thereto and havinga recess therein, a pedal having a longitudinal slot cut into the rearend thereof which receives the standard and forms a pivotal point forthe pedal, a thumb-screw vertically mounted in the standard so as toseat itself on the transverse pin in the pedal when said pedal is inposition, a jam-nut adapted to lock said thumb-screw when the parts havebeen adjusted, substantially as shown and for the purposes set forth.

2. In a pedal-action for pianos, in combination with the mainpiano-body, standards having recesses formed therein, pedals removablysecured to said standards by means of a slot cut into the rear end ofthe pedals and a transverse pin which engages with the recesses in thestandards, a series of notches cut into the under and central portion ofthe pedals, a longitudinal slot centrally located in the pedals whichtransverses the notches, a vertical rod, having its ends formed intoelongated heads, connecting the pedal with the bell-cranks, the lowerend of the rod engaging with the notches in the pedals and the upperends'engagingwith the cups formed in the outer ends of the bell-cranks,whereby the leverage of the pedals may be regulated, substantially asshown and for the purposes set forth.

3. In a pedal-action for pianos, in combination with the mainpiano-body, standards rigidly secured to said body, vertical slots cutin the upper ends of said standards, bellcranks having integraldownward-projecting ribs which engage with the slots in the standards,pins 16 rigidly secured to and set in a transverse manner to thebell-cranks and adapted to rest in notches formed in the upper ends ofthe standards transversely from the main slots, whereby a pivotal pointis secured for the bell-cranks, a series of holes formed in thebell-cranks thereby providing a means for their adjustment, cups formedin the outer ends of the bell-cranks, which receive the elongated headsof the vertical rods, a longitudinal slot in the outer ends of thebell-cranks through which the upright rods operate, substantially asshown and for the V purposes set forth.

4:. In a pedal-action for pianos,"in combination with the mainpiano-body, a bell-crank 20 mounted in a standard and similar to thecrank 12 except that it stands in an opposite direction thereof, thesaid cranks being connected by means of an adjustable rod, a pin passingtransversely through the bell-crank 20 and resting in vertical slots inthe standard 22, the ends of said pin extending out from each side ofthe standard .22, a spring passing across the face of the standard andbehind the projecting ends of the pin, and extending in an uprightmanner parallel with the perpendicular portion of the bell-crank, theupper ends of the spring bent at right angles with the main bodythereof, the said ends resting on the face of said perpendicular portionof the bell-crank, substantially as shown and for the purposes setforth.

5. In a pedal-action for pianos, in combination with the mainpiano-body, a bell-crank having an extended rib carrying a series ofopenings foradj usting said crank, a standard rigidly secured to theframework of the piano, the said standard having a longitudinal verticalslot cut therein, the said slot adapted to receive the extended integralrib on the crank, a cup formation on the outer end of the horizontalportion of the bell-crank 20, the said cup engaging with the lower endof an upright rod 24, a pin in the end of the rod 24c which extendsdownward and through a horizontal slot in the end of thebell-c1'ank,whe1'eby said rod is prevented from being displaced in alateral manner, when said rod is actuated by said crank, substantiallyas shown and for the purposes set forth.

6. In a pedal-action for pianos, in combina tion with the mainpiano-body, standards secured to said body having a horizontal slotterminating in a recess therein, pedals removaoly secured to saidstandards by means of transverse pins in the pedals engaging with therecesses in the standards, thumb-screws vertically mounted in thestandards and adapted to rest on the transverse pins when the pedals arein position, jam-nuts on said thumb-screws whereby said screws aresecured when the parts have been adjusted.

In witness whereof I have hereunto set my hand and seal, atIndianapolis, Indiana, this 20th day of June, A. D. 1899.

JOHN DIERDORF. [L. s.]

Witnesses:

J. FROHLIGER, F. W. WOERNER.

